One of the more commercially successful innovations in surgical procedures in recent years is the development of surgical stapler devices. These devices are designed to simultaneously cut and seal an extended segment of tissue in a patient, vastly reducing the time and risks of such procedures. Typically, a surgical stapler comprises two stapler arms, one containing one or more lines of multiple staples and a second containing a corresponding structure to bend each of the staples into a closed position. For many applications, a surgical blade is included in the device to quickly sever tissue between the lines of staples. Those stapler devices employing a cutting blade are referred to as “anastomotic staplers” and those used without a cutting blade are referred to as “non-anastomotic staplers.”
In the operation of a typical anastomotic stapler, the two stapler arms are positioned around tissue to be cut and then locked firmly together. In one motion, the user actuates the stapler device, which simultaneously installs two or more lines of staples through the tissue and cuts a line down the middle of the staple lines. In this manner, the user can quickly cut and seal tissue at the same time. This procedure is much faster than using a conventional process of cutting with scissors or a scalpel and then laboriously sealing the incision with sutures. As a result, patient care is dramatically improved by minimizing bleed time from the surgical site and significantly increasing the speed with which an operation can be completed.
For some procedures, the use of bare staples, with the staples in direct contact with the patient's tissue, is generally acceptable. The integrity of the tissue itself will normally prevent the staples from tearing out of the tissue and compromising the seam before healing has occurred. In certain circumstances, however, the tissue that is being sealed is too fragile to securely hold the staples in place. In these instances, the tissue will tend to rip at or near the staple lines, slowing healing and possibly leading to serious complications.
One area where fragile tissue is of particular concern is the use of stapler devices in lung tissue, and especially lung tissue that is affected by emphysema or similar condition. Diseased lung tissue is very fragile and, in extreme cases, will readily tear through unprotected staple lines. With the growing use of surgical staplers in operations on diseased lung tissues such as bullectomies and volume reduction procedures, it has become increasingly important to develop some reliable means to protect fragile tissue from tissue tears due to surgical staples or surgical stapling procedures. Moreover, when staples are used, it is desirable to reduce any leakage around the staples.
It is known to use bovine pericardial tissue as a staple line reinforcement sleeve. During an operation, a surgeon staples and cuts through both the bovine pericardial tissue and the patient's lung tissue in order to perform the lung resection procedure. Once the staples are in place, the surgeon must then cut the suture lines holding the bovine pericardial strips in place and remove the polyethylene backing material and sutures.
Other staplers such as endoscopic staplers present other difficulties. An endoscopic stapler is constructed to allow the stapler to be inserted through a small incision and then operated remotely within a patient's body by the surgeon. To accomplish this, most endoscopic staplers comprise shorter stapler arms (or “jaws”) that are connected together on a fixed pivot point in a scissors fashion. The stapler arms are generally mounted remote from the surgeon's actuation means through an extended staff.
This construction presents a number of unique problems. First, it has been found that the scissors-like construction of the stapler arms tends to entrap tissue within the pivot point. This can cause fouling problems within the pivot point. Additionally, the remote nature of the endoscopic stapler can make removal of excess reinforcement material difficult from the surgical site. Finally, secure retention of reinforcement material on remote arms is a major concern for a surgeon.
In light of these problems, it is one purpose of the present invention to provide an improved staple line reinforcement material for use on a stapler that will fully protect surgical staple lines while being easy to prepare and use. It is another purpose of the present invention to provide an improved staple line reinforcement material that addresses problems unique to endoscopic staplers. These and other purposes of the present invention will become evident from review of the following specification.